One change applied to an assembly instance, addressed by a path of template
ids from the assembly root down to the target (a chain so nested instances
disambiguate; length 1 — just the root — targets the instance root itself).
componentId fields name a template component id (stable in the assembly).
addObject / addComponent payloads carry instance-local ids that are not
template ids; "apply to source" promotes them.
One change applied to an assembly instance, addressed by a
pathof template ids from the assembly root down to the target (a chain so nested instances disambiguate; length 1 — just the root — targets the instance root itself).componentIdfields name a template component id (stable in the assembly).addObject/addComponentpayloads carry instance-local ids that are not template ids; "apply to source" promotes them.